1. Field of the Invention
The present invention relates to an exposure computation system wherein a computation is carried out with frequency information which corresponds to the exposure factors.
2. Description of the Prior Art
Generally, in an auto exposure computation system, the light information of the object to be photographed is transformed into a current or voltage value and is condensed logarithmically in order to enable electrical computation.
An ASA value and a diaphragm value are applied to an operation circuit, and the output of this operation circuit and a threshold voltage generating circuit are applied to a comparator circuit to compare them. When a coincidence occurs, the comparator circuit generates a signal which drives a driver circuit, such as a magnetic driver.
However, in conventional systems of this type wherein the threshold voltage generating circuit is used, it is difficult to change over the shutter speed presetting system and the diaphragm aperture presetting system. Additionally, the computation circuit is complicated and accordingly, the application of electronics to the camera is deemed insufficient.